Machine for forming plastic coated paperboard containers and erecting and deliveringmeans therefor



Sept. 21, 1965 c. z. MONROE ETAL 3,207,049

AINERS MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONT AND ERECTINGAND DELIVERING MEANS THEREFOR l0 Sheets-Sheet 1 Original Filed Nov. 7.1960 menu: 0 n no 8 Mir Charles CYYLO7I-V qzaw B. lgle m W44, 7%, Va! 0*M Sept. 21, 1965 c. z. MONROE ETAL 3,207,049

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p 21, 1965 c. z. MONROE ETAL 3, 07,049

MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. '7. 1960 10Sheets-Sheet 3 Illllllll Illlllllllllllllllllllll "l1 I Sept. 21, 1965c. z.

ONROE ETAL 3,207,049

MACHINE FOR F .ING P TIC COATED PAPERBOARD CONTAINERS A ER ING ANDDELIVERING MEANS THEREFOR Original Filed Nov. 1960 10 Sheets-Sheet 4 FIG5 mvswromd Ckqrleo Z. nlcwu' 7-4cnrr5 J5. glcdt' m wr ,W, a

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MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. 7. 1960 10Sheets-Sheet s p 1965 c. z. MONROE ETAL 3,207,049

MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. 7, 1960 10Sheets-Sheet 6 144 FIG. 8 f, o6

MVSMTORJ Ckourleu Z. YYK gun's 1B. lgl -f m 0 94%, VJ. M

q-roME-Yw p 21, 1965 c. z. MONROE ETAL 3,207,049

MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. 7, 1960 10Sheets-Sheet 7 O n V a Z09 201 I 195 I; I412], .t z nf v fi I l 1' 1 l kI I l a 1 o 162. \84' 192. $94 190 R m CkarLe z. nkowv'oe Harv: 13liledcom W, WV a 3,207,049 ASTIC COATED PAPERBOARD CONTAI n DELIVERINGMEANS THEREFOR NERS Sept. 21, 1965 c. z. MONROE ETAL MACHINE FOR FORMINGPL AND ERECTING AN Original Filed Nov. 7, 1960 10 Sheets-Sheet 8MVEDMTOKJ lzs Z3. Lc QJQWCZSB, lgledtifi'p wry, M. an aw Sept. 21, 1965c, z, MONROE ETAL 3,207,049

MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. 7, 1960 10Sheets-Sheet 9 m I FIG. l3 m ug I 250 cjl-r-romEP/ Sept. 21, 1965 c. z.MONROE ETAL 3,207,049

MACHINE FOR FORMING PLASTIC COATED PAPERBOARD CONTAINERS AND ERECTINGAND DELIVERING MEANS THEREFOR Original Filed Nov. 7, 1960 10Sheets-Sheet 1O CAqvleJ Zj YYLonv'oQ Q-lqrrg 13. asledtcm CRYTQRMEY/United States Patent 3,207,049 MACHINE FOR FORMING PLASTIC COATEDPAPERBOARD CONTAINERS AND ERECT- ING AND DELIVERING MEANS THEREFORCharles Z. Monroe, Detroit, and Harry B. Egleston, Livonia, Mich.,assignors to Ex-Cell-O Corporation, Detroit, Mich., a corporation ofMichigan Original application Nov. 7, 1960, Ser. No. 67,842, now PatentNo. 3,120,089, dated Feb. 4, 1964. Divided and this application July 3,1963, Ser. No. 303,699 17 Claims. (Cl. 93-441) This application is adivision of our copending application Serial No. 67,842, filed November7, 1960, now Patent No. 3,120,089, issued February 4, 1964, and theinvention herein relates to carton forming machinery and, morespecifically, to a novel machine for forming, erecting and deliveringplastic coated gable top containers of paperboard or the like. Themachine finds particular, but not exclusive, utility in producing filledand sealed cartons from flat collapsed blanks of paperboard or the likehaving a thermoplastic moistureproof coating on their inner and outersurfaces.

One illustrative form of carton adapted to be processed by the machinedisclosed and claimed herein is shown in Egleston et al. copendingapplication Serial No. 136,505, filed in the United States Patent Otficeon September 7, 1961, now Patent No. 3,120,335, issued February 4, 1964.More detailed information on such carton may, of course, be had upondirect reference to such application. For present purposes, however, itwill suffice to note that the container or carton disclosed therein ismade of high grade paperboard stock coated on both sides with athermoplastic material such as polyethylene. The polyethylene coating onthe paperboard is utilized not only as a moistureproofing material butalso serves as a heat and pressure sensitive adhesive which cooperatesin sealing the closure elements of the container so as to make afluidtight package. Because sealing involves the application ofconsiderable heat and pressure, suitable precautions must be taken toavoid damaging the polyethylene coating as the cartons are erected andsealed. Major reasons for this are the relatively low melting point ofpolyethylene and its tendency to stick to heated surfaces.

One object of the present invention is to provide a high speed,automatic, precision machine for receiving stacked carton blanks ofpaperboard or the like each having a thermoplastic coating such aspolyethylene on both sides and for forming such blanks successively intoerected and filled cartons having tightly sealed top and bottom closuresby utilizing the thermoplastic coating as an adhesive.

Another object of the invention is to provide a machine of the characterset forth and which will be adapted to fuse and seal the coated closureelements of the carton without damaging the moistureproof integrity ofthe thermoplastic coating thereon.

Still another object of the invention is to provide a machine of theforegoing type and which will efiiectively maintain the sanitaryintegrity of the carton from its initial stage as a flat collapsed blankuntil it emerges from the machine as a filled and sealed carton.

Other objects and advantages will become apparent in the light of thefollowing detailed description, taken together with the accompanyingdrawings, wherein:

FIGURE 1 is a perspective view of an illustrative carton forming machineembodying the present invention.

FIG. 1a is a plan view of a flat collapsed carton blank in the form inwhich it is presented to the machine of FIG. 1 for processing.

FIG. 2 is a perspective view of an erected, filled and sealed carton inthe condition in which it is discharged Patented Sept. 21, 1965 from themachine of FIG. 1 upon completion of its processing.

FIG. 3 is a bottom view of the carton of FIG. 2.

FIGS. 4a and 4b are companion diagrammatic views which together presenta plan view of the main drive system of the machine.

FIG. 5 is a diagrammatic perspective view illustrating the carton pathand sequential positions of the carton as it passes through the machineincident to being processed therein.

FIG. 6 is an enlarged perspective view showing the inside face of theblank of FIG. 1a, the blank being opened out flat for purposes of betterillustration.

FIG. 7 is an enlarged fragmentary perspective view showing the bottomclosure elements of the blank and carton of FIGS. 1a, 2, 3 and 6.

FIG. 8 is an end elevational view of the mandrel wheel assembly of themachine including various associated units for operating on the cartonat different stations along its path of movement.

FIGS. 9 and 10, respectively, are enlarged fragmentary views, inperspective and end elevation, respectively, detailing the bottombreaker mechanism.

FIG. 11 is a fragmentary elevational view showing a portion of themandrel wheel assembly and the cooperating heater arrangement forpreparing the bottom closure flaps for sealing.

FIG. 12 is an enlarged fragmentary sectional view through one of themandrels and heating elements taken in the plane of the line 12-12 inFIG. 11.

FIG. 13 is an enlarged fragmentary transverse sectional view taken inthe plane of the line 1313 in FIG. 8 and showing a portion of the bottomclosing mechanism and its associated drive.

FIG. 14 is an enlarged fragmentary vertical sectional view taken in theplane of the line 14-14 in FIG. 13 and detailing the manner in which thebottom closing unit tucks and closes the bottom flaps of the carton.

FIG. 15 is an enlarged fragmentary vertical sectional view through thecarton bottom taken in the plane of the line 15--15 in FIG. 14.

FIG. 16 is a view corresponding to FIG. 15 but with the carton bottomelements in completely closed and sealed condition.

FIG. 17 is an enlarged fragmentary side elevation showing a portion ofthe rotary top breaker mechanism with a carton in place thereon.

FIG. 18 is an enlarged fragmentary vertical sectional view through theupper portion of the carton and certain rotary breaker elements.

FIG. 19 is an enlarged fragmentary perspective view showing the upperportion of the carton after it emerges from the top breaker mechanism.

While the invention is susceptible of various modifications andalternative constructions, certain illustrative embodiments have beenshown in the drawings and will be described below in considerabledetail. It should be understood, however, that there is no intention tolimit the invention to the specific forms disclosed, but, on thecontrary, the intention is to cover all modifications, alternativeconstructions and equivalents falling within the spirit and scope of theinvention as expressed in the appended claims.

Referring more specifically to FIG. 1, the invention is thereexemplified in an illustrative machine 50 adapted to receive a supply offlat collapsed blanks 51 such as shown in FIG. In, process themautomatically at high speed, and to discharge them in the form of filledand sealed cartons 52 such as the one illustrated in FIG. 2. Beforepresenting a detailed description of the machine 50, however, it wouldbe desirable to outline briefly the salient features of the carton blank51 and the carton 52 processed by the machine 50.

As shown more particularly in FIGS. la, 2, 3, 6 and 7, it will be notedthat the carton 52 comprises a tubular body 54 of generally rectangularcross section having a bottom closure 55 and a top closure 56. Both thetop and bottom closures are formed from integral extensions of thecarton body and are held and sealed together in a manner which takesfull advantage of the properties of the thermoplastic coating on thecarton material.

The carton 52 is fashioned from a fiat blank of paperboard or the likecoated on both sides with thermoplastic material such as polyethylene,as pointed out earlier herein. The blank is divided by means of anappropriate pattern of score lines into a plurality of panels and areaswhich are utilized for the walls and the closure parts of the carton.Upon reference to FIG. 6, which illustrates the inner face of the blank,it will be noted that the body portion of the carton is defined by fourside panels 58, 59, 60, 61 and a side seam flap 62 which is adhesivelysecured to the inner face of the side panel 53.

The bottom closure 55 is defined in part by a pair of major bottompanels 64, 65 which are integral extensions of alternate side panels 58,60, and in part by a plurality of minor triangular panels 66, 67, 68 and69, 70, 71 which are integral extensions of alternate side panels 59,61. All of the bottom closure panels are integral parts of the lank andadjacent ones are separated from each other only by score lines whichultimately define the various folds or creases required to completeformation of the bottom closure. When the bottom closure is formed, thetriangular panel 66, 69 fold inwardly toward one another and therespective pairs of smaller triangular panels associated with them foldback against the inner faces of the major bottom panels 64, 65. Theprojecting lateral edges 72 of the panel 64 are chamfered slightly,defining in the projecting portion of the panel 64 a tuck-in flap 64awhich is inserted between the inner face of the major bottom panel 65and the triangular foldback panels 68, 70 which tend to fold back towardthe inner face of the panel 65. The bottom closure parts, when fullyinfolded, are pressed fiat and heat sealed in this position, asillustrated in FIG. 3. Any potential leakage channels between folds, orexposed raw edges of the blank, are sealed as by means of linear shapedembossments 74, 75, and by transversely disposed embossments '76 in theshape of relatively short rectangular notches (FIG. 3).

The top closure 56 (FIG. 2) has substantially a gable top configurationcomprising a pair of inclined roof panels 78, 79 surmounted by anupstanding top rib 80, defined in part by rib panels 81, 82. Interposedbetween the roof panels are triangular end panels 84, 85 each connectedrespectively to a pair of triangular foldback panels 86, 87 and 88, 89.Each pair of foldback panels is also connected to a corresponding pairof inner rib panels 90, 91 and 92, 93.

The top closure of the carton 52 also includes an extensible pouringspout which, in this instance, happens to be defined by triangular endpanel 84, foldback panels 86, 87 and inner rib panels 90, 91. Initially,the spout is disposed in collapsed condition within the top closure andprotectively sealed by means of sealing panels 81a, 82a which areabuttingly secured together along the entire length of the top rib. Tofacilitate easy opening of the carton 52 and accessibility of thepouring spout, the pouring edges of the latter, together with the majorareas of the inner rib panels 90, 91, may be covered with a patch or lip94- of adhesive material. By this is meant material which will not bondto itself or to the thermoplastic coating on the surfaces of the blankduring heat sealing of the top closure. Consequently, upon applicationof upward and outward thumb pressure to the infolded triangular panels86, 87 under the inclined roof panels 78, '79, the bond between sealingpanels 81a, 82a and the outer ends of the inner rib panels 90, 91becomes torn or fractured,

rendering the spout accessible and permitting the same to be sprung intoits outwardly extended position ready for pouring.

General machine organization Referring more particularly to FIGS. 1 and5, the illustrative machine 50 is adapted to receive a supply of fiatfolded tubular blanks 51 such as the one illustrated in FIG. 1a anddescribed earlier herein. The blanks are stacked, top down, in amagazine from which they are successively withdrawn by means of afeeder, erected into open-ended tubular form and loaded onto amulti-station bottom forming mechanism which forms and heat seals thebottom closure. Following the formation of the bottom closure, theblanks are successively transferred to a rotary top breaker mechanismand thence to a rotary filler mechanism. After filling, the blanks,which are partially completed cartons open at the top, are presented toa rotary steepler mechanism, resulting in further breaking or flexing ofthe top closure element about their score lines. The filled, opencartons are then conveyed beneath stationary top heater and closer unitswhich activate the thermoplastic on the top closure elements and bringthem together without applying any substantial pressure. The closedcartons are then presented to a rotary sealer unit which applies sealingpressure to the top closure elements. Following this, the filled andsealed cartons pass through a pair of dater rolls and are discharged ina continuous procession from the machine. For convenience, the partiallycompleted cartons will be designated by the reference numeral 51 attheir various stages of completion in the machine, and by the numeral 52upon emergence from the machine as a finished product.

The machine 50 comprises a console 95 supported on legs 96 and suppliedwith utilities such as electric power, compressed air, and cooling waterfrom appropriate external sources. A magazine loader 98 and magazine 99are mounted on top of the console at one end of the machine. Operativelyassociated with the magazine and adjacent to it are a feeder mechanism100 and a loader mechanism 101. On the side of the console below thesemechanisms is the operators control panel 102 for the machine and anemergency stop bar 104. To the left of the control panel 102 (as viewedin FIG. 1) and beneath the magazine loader 98, is the operatorsindicator panel 105. The latter reflects satisfactory or unsatisfactoryperformances of the various units throughout the machine so that troublespots can be quickly pinpointed and corrected.

Bottom forming mechanism 106 is situated roughly between the indicatorpanel 105 and the loader 101, being housed within an appropriateprotective enclosure. The mechanism 106 is adapted to receive blankssuccessively from the loader 101, top down, and to move them fromstation to station in an orbital path to form their bottom closure. Theblanks are then ejected and presented to a transfer receptacle whichshifts them from a horizontal to a vertical position and presents themto a rotary top breaker unit 108 on top of the console. From this pointon, the cartons remain above the top of the console.

The rotary top breaker unit 108, which happens to rotatecounterclockwise when viewed from the top, presents the open top cartonto rotary filler unit 109. The latter, which rotates clockwise whenview-ed from the top, fills the cartons successively and presents themto a main conveyor 110. The main conveyor thereupon moves the filledcartons. Still open at the top, under a rotary steepler mechanism 111,and thence under stationary top heater and closer units 112, 114. Fromhere, the filled and closed cartons are transferred to a rotary topsealer unit 115. After final sealing on the latter, the filled andcompleted cartons are passed through dater rolls and discharged from themachine.

The magazine and magazine loader 99 and 98, respectively, comprise thesubject matter of our copending divisional application, Serial No.297,482, filed concurrently herewith. It will suffice for the presentpurposes, therefore, to note that a magazine and magazine loader areprovided for assuring the presence of a supply of collapsed blanks atall times during the operation of the machine. The feeder and loadermechanisms 100, 101 are adapted to withdraw blanks successively from themagazine, erect them into open-ended tubular form, and then load theminto the bottom closing mechanism 106. For such purpose, thesemechanisms are driven in synchronism with each other from the main driveof the machine.

Bottom forming mechanism The bottom forming mechanism 106 (FIGS. 4a and8) comprises an intermittently driven mandrel assembly 142 carrying aplurality of radially disposed mandrels 141, in this instance ten innumber, and a plurality of cooperating station units with which themandrels are adapted to register sequentially during the course of theirintermittent or indexing movement. These station units are a bottombreaker unit 144, a plurality of heater units 145, 146, 147, a bottomclosing unit 148, and two bottom sealing units 149, 150. Both themandrel assembly and the station units are supported on a relativelyheavy upright frame panel 151 within the machine console.

The mandrel assembly 142 comprises a relatively large diameter hollowshaft 152 journaled in an appropriate bearing 154 carried by the framepanel 151 and projecting substantially beyond both faces of the latter.The end of the shaft 152 extending toward the control panel side of themachine has fixed thereto a large polygonal hub 155. In the presentinstance, the hub 155 has ten equally spaced annular seats on its outersurface and which receive the inner end portions of the mandrels andtheir mounting flanges 156. Each mandrel is constructed with a coolingchamber 158 (FIG. 8) adjacent its outer end to preclude adhesion betweenthe end face of the mandrel and the bottom closure parts of the carton51 being formed thereon. Water or other suitable fluid coolant iscirculated through the chambers 158 via supply and exhaust conduits 159,160 in each mandrel which may be connected in any suitable manner withcoolant supply and exhaust lines 161, 162 (FIG. 4a) through the hollowshaft 152.

Power for driving the mandrel assembly 142 with a step-by-step indexingmotion is furnished by main drive motor 164 of the machine via chain andsprocket drive 165 and main drive shaft 166. The latter has fixedthereon a barrel cam 168 which drives a spider wheel 169 keyed orotherwise secured to the mandrel assembly shaft 152. The track of cam168 includes suflicient dwell so that the spider 169, through itsfollower rollers 170, is given an intermittent angular motion which is,of course, imparted to the mandrel assembly.

Following the loading of an open-ended carton blank 51 on the mandrel bythe loader mechanism 101, top down, the mandrel assembly moves the blankthrough two indexing steps, the second step bringing the blank intoregister with the bottom breaker unit 144 (FIGS. 8, 9 and In thisposition, all the bottom closure panels overhang the end of the mandreland the common score line connecting them to the carton side panels isapproximately even with the end face of the mandrel. The major bottompanel 65 is in leading position and the other major bottom panel 64 isin trailing position with respect to the direction of mandrel movement.Minor triangular panels 66, 67 and 68 face the operators side of themachine, while minor triangular panels 69, 70, 71 face the main framepanel 151.

The bottom breaker unit 144 is adapted to effect substantial prebendingof the bottom closure parts on their respective score lines and towardtheir closed position. The prebending action is carried to a sufficientextent to create along each score line, in so far as possible, a

permanent set in the paperboard and its thermoplastic coating. Thisgreatly facilitates the subsequent closing and sealing of the bottomclosure elements of the blank.

As illustrated in FIGS. 10 and 12, the bottom breaker unit 144 comprisesa relative heavy bridge or frame member 171 fixed to the main framepanel 151 in generally overlying relation with the mandrel assembly 142.The bridge member 171 carries a crosshead 172 and fixed to a guideplunger 174 and both mounted for reciprocation along a projection of theradial axis of the underlying registered mandrel. Depending from theunderside of the crosshead 172, and adapted to cam the major bottompanels 64, 65 inwardly as the crosshead approaches the end face of themandrel, are a pair of folder wings 175, 176 (FIGS. 8 and 9). In thepresent instance, the folder wings 175, 176 are fashioned as stampedplates of relatively heavy guage sheet metal fixed to the underside ofthe crosshead 172 in any suitable manner.

Pivotally mounted on the bridge 171, and adapted to exert inward foldingpressure on the minor triangular panels 65 and 66 as the crossheaddescends with the folder wings 175, 176, are a pair of triangularfolding fingers 178, 179. The latter may also be fashioned as stampingsof relatively heavy gauge sheet metal. The fingers 178, 179 are fixed asby means of mounting blocks 180, 181 to respective ones of a pair ofrock shafts 182, 184 journaled on the bridge 171 in straddling relationwith the other end of the mandrel. Each of the rock shafts 182, 184 hasan end portion extending beyond the bridge 171 and carrying acorresponding one of a pair of rocker arms 185, 186. The latter haveadjacent their projecting ends follower bosses or rollers 188, 189 whichengage corresponding ones of cam tracks 190, 191 in depending cam arms192, 194 fixed to the crosshead. In the present instance, the armshappen to be integral parts of a bifurcated plate member 195 rigidlyfixed to the left-hand end of the crosshead (as viewed in FIG. 8). Byreason of this connection, it will be appreciated that the fingers 178,179 are rocked inwardly as the crosshead approaches the mandrel facewith the wings 175, 176, and outwardly as the crosshead and wingsretreat from the mandrel face.

For the purpose of driving the crosshead, folder wings and folderfingers in timed relation with the mandrel assembly so that the foldingof the bottom closure panels will occur while the mandrel dwells inregistered position with the bottom breaker unit, the latter isconnected to the main drive shaft 166. The drive comprises a chain andsprocket take-off 196 from the main drive shaft 166 and which rotates asmall crank shaft 198 journaled in a boss 199 fixed on the rear side ofthe main frame panel 151 (FIGS. 40 and 10). The boss 199 is mounted onan outwardly extended arm 200 fixed in any suitable manner to the framepanel 151. The crankshaft 198 has fixed thereon a crank arm 201 which inthis instance is drivingly connected to a rocker arm 202 by means of anangularly disposed, adjustable swivel link 204. The rocker arm 202 ispivotally mounted on brackets 205 fixed to the frame panel 151 andextends through aligned slots 206, 208 in the panel 151 and rear wall ofbridge 171. The forwardly extending end of rocker arm 202 is formed witha slot 209 which engages a pin 210 fixed between a pair of lugs 211 onthe crosshead 172. By reason of this arrangement, rotation of thecrankshaft 201 will effect oscillation of the rocker arm 202 and this,in turn, will effect reciprocation of the crosshead 172 and the partsassociated therewith. Even though there is a small amount of angularitybetween the plane of rotation of the crank 201 and the plane ofoscillation of the rocker arm 202, the swivel link 204 provides adequateaccommodation.

Following the bottom breaking operation, the mandrel assembly indexesthe carton 51 around to the heater stations 145, 146 and 147. In orderto avoid overheating of the bottom with possible damage to thepaperboard or the thermoplastic coating, and yet drive sufficient heatinto the bottom closure panels to achieve effective sealing, resort ishad to a series of heating stations, in this instance, three in number(FIGS. 4a, 8, 11 and 12). These stations are substantially identical andare adapted to apply warm air to both sides of the bottom closure panelsso as to raise their temperature sufliciently to activate the adhesiveaction of the thermoplastic coating on the carton blank. Wherepolyethylene is used as such coating, the temperature of the blank mustbe increased to approximately 350 to 500 degrees Fahrenheit.

As shown more particularly in FIGS. 11 and 12, each heater stationcomprises a hollow boxlike heater head 212 fixed to the main frame paneland adapted to nestingly straddle the radially projecting bottom closurepanels of the carton 51 as it is held in position by an underlyingregistered mandrel. For this purpose, the head 212 includes a tunnel 214which receives the bottom closure panels and which is defined by aplurality of perforated walls 215, 216 and 217. Each of the latter has aseries of relatively small diameter nozzle passages 218 arranged inspaced relation over its face area and adapted to apply warm air to theadjacent bottom closure panels of the blank. Air is supplied to thepassages 218 from a plenum chamber 219 within the head. The relativeamount of air discharged from the passages 218 of any of the walls 215,216, 217 may be suitably regulated as by means of baffles 220 in thechamber 219.

Air is supplied to the heater heads 212 from a blower 221 mounted nearthe lower left corner of the frame panel 151 as viewed in FIGS. 4a and11. The blower 221 discharges into a vertical manifold 222 whichconnects at vertically spaced points with three separate combustionchambers 224. The latter are connected to respective ones of the heads212 via individual supply ducts 225, 226 and 227 (FIG. 11) whichcommunicate respectively with the plenum chamber of each head.

Each combustion chamber 224 includes an appropriate gas burner andigniter (not shown). Each burner is supplied with an appropriate mixtureof air and gas from an external supply via a control valve 228 andbranch line 229. Combustion is, of course, carefully controlled so as tobe as complete as possible. With an excess of air (as far as the burneris concerned) supplied to the burner, the combustion products mix withthe excess air in the combustion chamber, resulting in the discharge ofa blast of heated air at each heater head 212 having, in the presentinstance, a temperature of about 800 degrees Fahrenheit. By the time theblank 51 is ready to leave the last heater station 147, its bottomclosure panels have been heated to a temperature of 350 to 500 degreesFahrenheit and are ready for closing and sealing.

Provision is made for automatically reducing the temperature and amountof warm air discharged from the heater heads 212 to prevent thermaldamage to the carton blanks thereunder in event of a temporary stoppageof the machine due, for example, to a jam at some transfer point. Thisis accomplished in part by curtailing the amount of air supplied by theblower 221 and in part by curtailing the amount of gas supplied to theburners of the combustion chamber. Referring further to FIG. 13, it willbe noted that in the present instance a shut-down bafile 230 isinterposed in the manifold 222 between the blower 221 and the firstoutlet opening. The bafile 230 is fixed to a rocker arm 231spring-biased to hold the bafile in a normally open position. The rockerarm 231 is also connected to an actuator 232, which may be a solenoid oran air cyl inder, related to the main drive control in such a mannerthat it shifts the rocker arm and baffie to a shutdown position uponstoppage of the machine. By the same token, the air-gas control valves228 are similarly related to the main drive control so as to shift to ashutdown position concurrently with, or slightly before, the baflle 230.

The shut-down position of both the baflie 230 and valves 228 in thiscase is such as to drastically curtail the flow of the air-gas mixture,and the secondary air, respectively. The bafile 230 and valves 228 shiftto open position, restoring the flow of air and gas, as an incident torestarting of the machine. In some instances, however, it may bepreferable for these members to stop the flow of air and gas altogetherduring stoppage of the machine. In that event, the burners are ignitedas an incident to restarting of the machine.

After the heating operation, the mandrel assembly indexes and carriesthe blank 51 from the last heater unit 147 to the bottom closing unit orstation 148 (FIG. 8). At this point, the bottom closure panels have beenheated to a temperature sufficient to activate the adhesive action oftheir thermoplastic coating. In such condition, the particular coatingused on the blank 51 will adhere to itself and to hot surfaces but notto cold surfaces of other material.

The bottom closing unit 148 (FIGS. 8, 13 and 14) comprises a supportblock 234 fixed to the lower portion of the frame panel 151. The supportblock carries a closer shoe 235 and its guide plunger 236, both mountedfor reciprocation approximately along a projection of the radius of theregistered mandrel. The upper face of the closer shoe 235 is concave ina direction transverse to the plane of rotation of the mandrel assembly,such shape being defined by two angular surfaces. One such surface isundercut with respect to the other, defining a transverse slot 238 and awedge-shaped tuck-in blade 239 in the central portion of the shoe (FIGS.8 and 14). Upon elevation of the shoe 235 toward the mandrel (FIGS. 13,14), the slot 238 is adapted to engage the projecting end of the majorbottom panel 65. At the same time, the blade 239 is adapted to engagethe major bottom panel 64 and to tuck it into the space between theinner face of the panel 65 and the adjacent triangular fold-back panels68, 70 (FIGS. 14, 15). The shoe 235 dwells in elevated position for asufiicient interval to permit withdrawal of the blade 239 from theclosed, tucked-in bottom as an incident to the next step of indexingmovement of the mandrel assembly.

For the purpose of assuring proper orientation of the bottom closurepanels on entering and leaving the closing station 148, the later isequipped with fixed arcuate guides 240, 241. The guide 240 is disposedto prevent jamming or tearing of the free lower end of the bottom panel64 against the edge of the shoe 235 when the same is in loweredposition. The guide 241, on the other hand, is arranged to hold theclosed bottom in that condition as the mandrel assembly moves it fromthe raised shoe 235 to the sealing station 149.

Provision is made for driving the closer shoe 235 to reciprocate inproperly timed relation to the mandrel assembly. For this purpose, themain drive shaft 166 has fixed thereon a face plate cam 242 (FIGS. 4aand 13). The latter drives, through follower roller 244, a reciprocatingplunger 245 slidably mounted in a fixed sleeve 246 to the rear of themain frame panel 151. The plunger 245 has rack teeth which mesh withpinion 248 fixed to cross shaft 249. The latter extends into the supportblock 234 and has another pinion 250 fixed thereon. The pinion 250, inturn, drivingly meshes with rack teeth on the guide plunger 236 ofcloser shoe 235 (FIGS. 8 and 13).

From the bottom closing unit 148, the blank 51 next passes to the bottomsealing units 149, 150. The latter are substantially identical and, inthis instance, two such units are used in order to subject the bottomclosure to pressure for the necessary total interval of sealing time. Asillustrated in FIG. 8, each sealing unit comprises a pressure pad 251having fluid coolant circulating therethrough via inlet and outletpassages 252 and 253. Each pressure pad is pivotally connected as by pin254 to a rocker arm 265 which is adapted to move it through a relativelyshort displacement between a pressure applying position where itsqueezes the bottom closure panels against the end face of the mandrel,causing them to assume the condition of FIG. 16, and an inactiveposition spaced farther away from the end face of the mandrel. Thepivotal mounting tends to give each pressure pad a limited amount offloat, permitting it to accommodate readily to the bottom closureelements of the blank 51 as it presses them against the end face of themandrel.

The rocker arms 255 are driven by respective ones of rock shafts 256 and258 which extend through the main frame panel 151 (FIGS. 4a and 8). Theinner ends of the rock shafts are respectively provided with crank armsconnected through appropriate links to an oscillating collar 259journaled on the mandrel assembly shaft 152 (FIG. 4a). The oscillatingcollar has fixed thereto a driiving arm 260 which carries a followerroller 261, the latter engaging the track of a barrel cam 262 rigidlysecured to the main drive shaft 166. Arcuate guide shoes 241, 264 and265 assure proper entry and exit of the carton 51 into and out ofregistry with each of the bottom closing units 149, 150 (FIG. 8).

Upon completion of the bottom sealing operation as described, the blankis transferred through a sanitizer unit 279 by the transfer mechanism266. The sanitizer mechanism may be of any suitable type, and may beemployed in those instances where local health regulations requireadditional precautions even though the machine maintains the sanitaryintegrity of the blank under normal operating conditions. From thesanitizer unit, the partially formed blank is transferred to a rotarytop breaker unit 108.

Rotary top breaker unit Turning now to FIGS. 1, 4b, 17 and 18, it willbe noted that the rotary top breaker unit 108 comprises a rotatingturret 294 mounted on top of the machine console 95. In this instance,the turret 294 has four carton receptacles, each defined by pairs oflaterally spaced bars 295 and a bottom support shelf 296. Arcuate guiderails 298 fixed on upright posts 299 prevent the cartons from fallingout of the receptacles as the turret rotates. The unit 108 is adapted toreceive cartons successively transferred from uprighting arm 286 alongguide rails 300 and to prebend the top closure panels of the partiallycompleted carton 51 along their various score lines. This isaccomplished in each carton as the latter moves from the transfer pointadjacent the guide rails 300 to another transfer point a little over 180away where the carton is presented to the rotary filler unit 109.

For the purpose of effecting such prebending as an incident to rotationof the turret 294, the latter is provided with a breaker head 301situated in overlying relation with each carton receptacle. Each breakerhead 301 in this case happens to be of inverted T-shape and is mountedon an upstanding plunger 302. The latter extends downwardly into thehousing of the turret 294 and carries a follower roller 304 whichengages the track of a relatively large fixed cam 305 within the turrethousing. Mounted in depending relation from each is head 301 andoverlying the associated carton receptacle is a bending anvil 306 havinga pair of opposed bending knees 308. The anvil 306 is supported as bymeans of bracket 309 fixed to the head and 9. depending stem 310 fixedto the bracket. Upon rotation of the turret, it will be perceived thatthe head 301 will descend under the action of the cam 305 until the headaccosts the housing of the turret 294, at which point the bending knees308 will be opposite the horizontal score line in the blank 51 whichseparates the side panels and the top closure panels.

For infolding the triangular end panels 84 and 85 of the top closure,the head 301 is provided with a pair of triangular folder fingers 311and 312 (FIGS. 1, 17 and 18). The latter are secured in any suitablemanner to a pair of laterally spaced rock shafts 314, 315 projectingoutwardly from the head 301 and adapted to fold the fingers 311 and 312inwardly toward the anvil 306 upon descent of the head 301. Such actionmay be accomplished by means of rack and pinion connections 316 betweenthe rock shafts 314, 315, and plunger 302 actuated by overrun of theplunger 302 further into the turret housing 294 after the head 301 hasdescended.

As a result of the foregoing action, the top closure panels of thecarton 51 are prefolded inwardly to a position approximating that shownin FIG. 19. In order to permit withdrawal of the anvil 306 from thecarton upon elevation of the head 301, the unit 108 is provided with astripper plate 318 for each receptacle. Each plate has a horizontalledge 319 overlying the top edge of the car ton and in position to stripit from the anvil 306 as the latter is elevated.

The turret 294 may be driven in timed relation with main drive shaft 166by any appropriate power take-off. In the present case, this comprisesbevel gears 320, 321, cam shaft 322 and spiral gears 324, 325 (FIG. 4b).

Having thus formed the bottom of the carton and passed the same throughthe rotary top breaker unit, the carton is in condition to be filled,closed and its top closure sealed.

We claim:

1. In a carton forming machine for receiving blanks of paperboard or thelike coated with thermoplastic material and having foldable end closurepanels defined therein, a forming mechanism comprising, in combination;a mandrel disposed for movement about an axis of rotation and adapted toreceive an open-ended blank thereon; means defining a plurality ofstations about said axis for successively folding, heating, closing, andsealing said end closure panels; means for moving said mandrel aboutsaid axis with an indexing motion for sequential registration with eachsaid station; said folding station including a bridge member adapted forregistration with said mandrel, a crosshead slidably mounted on saidbridge member for reciprocating movement relative to the end face ofsaid mandrel, a pair of folder wings fixed to the underside of saidcrosshead, a pair of folder fingers pivotally mounted on said frame, andmeans interposed between said crosshead and said fingers for rockingthem inwardly as said crosshead approaches said mandrel.

2. In a carton forming machine for receiving blanks of paperboard or thelike coated with thermoplastic material and having foldable end closurepanels defined therein, a forming mechanism comprising, in combination;a mandrel disposed for movement about an axis of rotation and adapted toreceive an open-ended blank thereon; means defining a plurality ofstations about said axis for successively folding, heating, closing, andsealing said end closure panels; means for moving said mandrel aboutsaid axis with an indexing motion for sequential registration with eachsaid station; said heating station including a heater dsposed forregistration with the end of said mandrel and adapted for registrytherewith, a tunnel in said heater facing said mandrel, and meansdefining outlet passages in the walls of said tunnel for dischargingwarm air against the blank closure panels on the mandrel.

3. In a carton forming machine for receiving blanks of paperboard or thelike coated with thermoplastic material and having foldable end closurepanels defined therein, a forming mechanism comprising, in combination;a mandrel disposed for movement about an axis of rotation and adapted toreceive an open-ended blank thereon; means defining a plurality ofstations about said axis for successively folding, heating, closing, andsealing said end closure panels; means for moving said mandrel aboutsaid axis with a step-by-step indexing motion for sequentialregistration with each said station; said closing station including acloser shoe adapted for registration with said mandrel, means defining atrans verse tuck-in blade in said closer shoe, means for reciprocatingsaid closer shoe between an initial position .clear of the bottomclosure panels and an active position engaging said bottom closurepanels and tucking one within the other, and means for causing saidcloser shoe to dwell in said active position as said mandrel and blankpass out of registry therewith.

4. In a carton forming machine for receiving blanks of paperboard or thelike coated with thermoplastic material and having foldable end closurepanels defined therein, a forming mechanism comprising, in combination;a mandrel disposed for movement about an axis of rotation and adapted toreceive an open-ended blank thereon; means defining a plurality ofstations about said axis for successively folding, heating, closing, andsealing said end closure panels; means for moving said mandrel aboutsaid axis with a step-by-step indexing motion for sequentialregistration with each said station; said closing and sealing stationsincluding means for closing said end closure panels, means including atleast one pressure pad for sealing said end panels after closure, andmeans on said mandrel and on said pressure pad for cooling both the endface of said mandrel and said pressure pad.

5. In a machine for forming cartons from blanks of paperboard or thelike having bottom closure panels defined therein, a bottom closurepanel breaker comprising, in combination, a mandrel, a bridge memberfixed to a support for registration with said mandrel, a crossheadslidably mounted on said bridge member for reciprocating movementrelative to the end face of said mandrel, a pair of folder wings fixedto the underside of said crosshead, a pair of folder fingers pivotallymounted on said frame, and means interposed between said crosshead andsaid fingers for rocking them inwardly as said crosshead approaches saidmandrel.

6. In a machine for forming cartons from blanks of paperboard or thelike having bottom closure panels defined therein, a bottom closurepanel breaker comprising, in combination, a mandrel, a bridge memberfixed to a support for registration with said mandrel, a crossheadslidably mounted on said bridge member for reciprocating movementrelative to the end face of said mandrel, a pair of folder wings fixedto the underside of said crosshead, a pair of folder fingers pivotallymounted on said frame, and means including a cam and follower interposedbetween said crosshead and said fingers for rocking them inwardly assaid crosshead approaches said mandrel.

7. In a machine for forming cartons from blanks of paperboard or thelike having bottom closure panels defined therein, a bottom closurepanel breaker comprising, in combination, a mandrel, a bridge memberfixed to a support for registration with said mandrel, a crossheadslidably mounted on said bridge member for reciprocating movementrelative to the end face of said mandrel, a pair of folder wings fixedto the side of said crosshead facing said mandrel, a pair of folderfingers mounted on rock shafts journaled on said frame, a pair of rockerarms on respective ones of said rock shafts, a follower on each saidrock shaft, a pair of cam arms fixed to said crosshead and slidablyconnected to said followers, said cam arms being adapted to shift saidrocker arms and rock shafts whereby said fingers are rocked inwardly assaid crosshead approaches said mandrel.

8. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having end closure panels defined therein, meansfor heating said closure panels to adhesively activate the thermoplasticcoating thereon and comprising, in combination, a mandrel movable aboutan axis and disposed generally radially thereof, a heater disposed forregistration with the end of said mandrel and adapted for registrytherewith, a tunnel in said heater facing said mandrel, and meansdefining outlet passages in the walls of said tunnel for dischargingwarm air against the blank closure panels on the mandrel.

I 9. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having end closure panels defined therein, meansfor heating said closure panels to adhesively activate the thermoplasticcoating thereon and comprising, in combination, a mandrel movable abouta fixed axis and adapted to carry a blank, and a plurality of heatersdisposed for registration sequentially with the end of said mandrel,each said heater having a tunnel facing said mandrel, each said heateralso having outlet passages in the walls of its tunnel for dischargingwarm air against the blank closure panels on the mandrel.

10. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having end closure panels defined therein, meansfor adhesively activating the thermoplastic coating on said closurepanels for heat sealing and comprising, in combination, a mandrelmovable about a fixed axis and adapted to receive a carton blank, aheater head disposed for registration with the end of said mandrel, atunnel in said heater head facing said mandrel, means defining outletpassages in the walls of said tunnel for discharging warm air againstthe blank closure panels on the mandrel, a combustion chamber, means forsupplying an air-gas mixture for burning in said combustion chamber,means for supplying sec ondary air to said combustion chamber, a conduitconnecting said combustion chamber to said heater head, and controlmeans responsive to stoppage of said machine for curtailing the fiow ofboth the air-gas mixture and the secondary air to prevent thermal damageto the blank 11. In a carton forming machine for thermoplastic coatedblanks of paperboard or the like having end closure panels definedtherein, means for adhesively activating the thermoplastic coating onsaid closure panels for heat sealing and comprising, in combination, amandrel movable about a fixed axis and adapted to receive a cartonblank, a heater head disposed for registration with the end of saidmandrel, a tunnel in said heater head facing said mandrel, meansdefining outlet passages in the walls of said tunnel for dischargingwarm air against the blank closure panels on the mandrel, meansincluding a combustion chamber for supplying warm air to said heaterhead, and adjustable bafiles in said head adapted to proportion the flowof warm air from each wall of said tunnel relative to the others.

12. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having major and minor bottom closure panelsdefined therein, the major panels extending beyond the bottom edge ofthe carton blank, a mandrel movable about a fixed axis, a closer shoeadapted for registration with said mandrel, means defining a transversetuck-in blade in said closer shoe, means for reciprocating said closershoe between an initial position clear of the bottom closure panels andan active position engaging said bottom closure panels and tucking onewithin the other, and means for causing said closer shoe to dwell insaid active position as said mandrel and blank pass out of registrytherewith.

13. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having major and minor bottom closure panelsdefined therein, the major panels extending beyond the bottom edge ofthe carton blank, a mandrel movable about a fixed axis, a closer shoeadapted for registration with said mandrel, means defining a tuck-inblade in said closer shoe, means for reciprocating said closer shoebetween an initial position clear of the bottom closure panels and anactive position with said tuck-in blade engaging said bottom closurepanels and tucking one within the other, means for causing said closershoe to dwell in said active position as said mandrel and blank pass outof registry therewith, a first fixed guide shoe mounted in closealignment with said initial position of said closer shoe on the sideapproached by said mandrel, and a second fixed guide shoe mounted inalignment with said active position of said closer shoe on the side fromwhich said mandrel recedes.

14. In a carton forming machine for thermoplastic coated blanks ofpaperboard or the like having heat sealable end closure panels, thecombination of a mandrel movable about an axis and adapted to carry acarton blank, means for heating said end closure panels of said blank toadhesively activate the thermoplastic coating thereon, means for closingsaid end closure panels, means including at least one pressure pad forsealing said end panels after closure, means for cooling the end face ofsaid mandrel, and means for cooling the end face of said pressure pad.

15. In a carton forming machine for handling blanks of paperboard or thelike having top closure panels defined therein, a top breaker unitcomprising, in combination, a rotatable turret, a breaker head mountedon said turret and reciprocable vertically thereon, a bending anvilmounted on said head in depending relation therefrom, a pair of opposedbreaker fingers rockably mounted on said head for coaction with saidbending anvil, a fixed cam Within said turret, a plunger connected withsaid fixed cam and said breaker head for reciprocating the lattervertically, and means for rocking said breaker fingers as an incident tosuch reciprocation.

16. In a machine for forming cartons from blanks of paperboard or thelike having top closure panels defined therein, a top breaker unitcomprising the combination of a rotatable turret, a breaker head mountedon said turret for reciprocation relative thereto, a bending anvilcarried on said head and spaced therefrom, a pair of opposed breakerfingers also carried on said head for coaction with said bending anvilin prebending the top closure panels of said blank, rockable mountingmembers on said head and fixed to said breaker fingers, a plungerslidably housed within said breaker head and adapted to support the sameat one end of its stroke, rack and pinion connections between saidplunger and said rockable mounting members, a stop on said turret forarresting the motion of said breaker head prior to completion ofmovement of said plunger, a fixed cam on said turret, follower meanscomiecting said fixed cam on said turret, follower means connecting saidfixed cam to said plunger, said fixed cam having a throw providingoverrun for said plunger after said head has engaged said stop wherebythe overrun of said plunger actuates said rack and pinion connectionsfor rocking said breaker fingers as an incident to such plunger overrun.

17. In a carton forming machine for handling blanks of paperboard or thelike having top closure panels defined therein, a top breaker unitcomprising the combination of a rotatable turret, a breaker head mountedon said turret for reciprocation relative thereto between a raised and alowered position, a bending anvil mounted on said head in projectingrelation therefrom, a pair of opposed breaker fingers rockably mountedon said head for coaction With said bending anvil, a fixed cam withinsaid turret, a plunger connected with said fixed cam and said breakerhead for reciprocating the latter vertically, means for rocking saidbreaker fingers as an incident to such reciprocation, and a strippermember fixed to said turret having an abutment positioned to accost thetop edge of a carton and strip the latter from said bending anvil assaid head returns to raised position.

References Cited by the Examiner UNITED STATES PATENTS 2,737,090 3/56Nordquist 9344.1 X

FRANK E. BAILEY, Primary Examiner.

1. IN A CARTON FORMING MACHINE FOR RECEIVING BLANKS OF PAPERBOARD OR THELIKE COATED WITH THERMOPLASTIC MATERIAL AND HAVING FOLDABLE END CLOSUREPANELS DEFINED THEREIN, A FORMING MECHANISM COMPRISING, IN COMBINATION;A MANDREL DISPOSED FOR MOVEMENT ABOUT AN AXIS OF ROTATION AND ADAPTED TORECEIVE AN OPEN-ENDED BLANK THEREON; MEANS DEFINING A PLURALITY OFSTATIONS ABOUT SAID AXIS FOR SUCCESSIVELY FOLDING, HEATING, CLOSING, ANDSEALING SAID END CLOSURE PANELS; MEANS FOR MOVING SAID MANDREL ABOUTSAID AXIS WITH AN INDEXIING MOTION FOR SEQUENTAIL REGISTRATION WITH EACHSAID STATION; SAID FOLDING STATION INCLUDING A BRIDGE MEMBER ADAPTED FORREGISTRATION WITH SAID MANDREL, A CROSSHEAD SLIDABLY MOUNTED ON SAIDBRIDGE MEMBER FOR RECIPROCATING MOVEMENT RELATIVE TO THE END FACE OFSAID MANDREL, A PAIR OF FOLDER WINGS FIXED TO THE UNDERSIDE OF SAIDCROSSHEAD, A PAIR OF FOLDER FINGERS PIVOTALLY MOUNTED ON SAID FRAME, ANDMEANS INTERPOSED BETWEEN SAID CROSSHEAD AND SAID FINGERS FOR ROCKINGTHEM INWARDLY AS SAID CROSSHEAD APPROACHES SAID MANDREL.